Randomized, Multicentre, Phase II Study Evaluating the Interest of Imatinib Treatment Maintenance or Interruption After at Least 10 Years of Treatment in Patients With Locally Advanced/Metastatic Gastrointestinal Stromal Tumors (GISTs)
This is a 2 arms study concerning patients under imatinib treatment for at least 10 years of treatment with locally advanced/metastatic GIST. In the first arm, patients will discontinue Imatinib treatment. This arm will allow to determine if the re-introduction of Imatinib at relapse is still an efficient treatment for the control of disease. In the second arm, patients will continue Imatinib treatment, allowing to determine if the continuation of this treatment is efficient for disease control, by the rate of non-progression disease.
• Patients ≥18 years of age;
• Histologically documented diagnosis of malignant advanced/metastatic GIST with immunohistochemical documentation of c-kit (CD117) expression either by the primary tumor or metastases;
• Eastern Cooperative Oncology Group (ECOG) - Performance status (PS) 0 to 2 evaluated within 7 days prior to the date of inclusion.
• Patient must be under imatinib treatment (at 300 or 400mg/day) maintained for 10 years or over with no more than 12 months in total or 3 consecutive months of interruption during the treatment period;
• Patient with controlled disease (without any progression under imatinib);
• Willingness and ability to comply with scheduled visits, treatment plans , laboratory tests, and other study procedures;
• Covered by a medical/health insurance;
• Signed and dated informed consent document indicating that the patient has been informed of all aspects of the trial prior to enrolment.